<template>
    请输入姓名:<input type="text" v-model="username">
    <div>姓名是：{{ username }}</div>
    <input type="text" v-model.number="num1">+<input type="text" v-model.number="num2">={{ num1+num2 }}
</template>

<script setup>
import{ref} from 'vue'
const username=ref('zhangsan')
const num1=ref(1)
const num2=ref(2)
</script>